{"gene":"IFT52","run_date":"2026-06-10T01:55:22","timeline":{"discoveries":[{"year":2001,"finding":"IFT52 localizes by immunofluorescence and immunoelectron microscopy to two horseshoe-shaped rings around the basal bodies, specifically associated with the periphery of transitional fibers, identifying transitional fibers as the docking site for IFT particles entering the flagellar compartment. The flagellaless bld1 mutant carries a deletion in the IFT52 gene and completely lacks IFT52 protein.","method":"Immunofluorescence, immunoelectron microscopy, cDNA cloning, genetic mutant analysis (bld1)","journal":"Current biology : CB","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct localization by immunoelectron microscopy with genetic confirmation via bld1 null mutant, replicated by immunofluorescence","pmids":["11676918"],"is_preprint":false},{"year":2010,"finding":"IFT52 directly interacts with IFT88 and IFT46 within the IFT-B core complex, and these three proteins together form a ternary complex. Chemical cross-linking confirmed the IFT52-IFT88 interaction. IFT52 is part of the ~500 kDa IFT-B core that also contains IFT88, IFT81, IFT74/72, IFT46, IFT27, IFT25, and IFT22.","method":"Yeast two-hybrid, bacterial coexpression, chemical cross-linking, biochemical fractionation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — multiple orthogonal methods (Y2H, bacterial coexpression, cross-linking) in a single study establishing direct binary and ternary interactions","pmids":["20435895"],"is_preprint":false},{"year":2014,"finding":"Crystal structures of IFT70/52 (2.5 Å) and IFT52/46 (2.3 Å) subcomplexes revealed that IFT52 residues 330–370 are buried within the IFT70 tetratricopeptide repeat superhelix; IFT88 binds IFT52 residues 281–329; and the IFT52C/IFT46C subcomplex is essential for IFT-B core integrity by mediating interaction between the IFT88/70/52/46 and IFT81/74/27/25/22 subcomplexes. Overexpression of mammalian IFT52C acts as a dominant-negative, causing IFT protein mislocalization and disrupted ciliogenesis in MDCK cells.","method":"X-ray crystallography (2.5 Å and 2.3 Å), in vitro reconstitution of nonameric IFT-B core, dominant-negative overexpression in MDCK cells","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — high-resolution crystal structures combined with biochemical reconstitution and functional cell-based validation","pmids":["25349261"],"is_preprint":false},{"year":2016,"finding":"IFT52 compound heterozygous mutations in a short-rib polydactyly syndrome patient result in reduced IFT52 protein, leading to reduced levels of IFT74, IFT81, IFT88, and ARL13B, a 60% reduction in cilia formation, and loss of cilia length regulation, demonstrating IFT52 is essential for anterograde IFT-B complex integrity and ciliogenesis.","method":"Patient cell studies, western blotting, immunofluorescence cilia quantification, whole-exome sequencing","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — patient cell-based loss-of-function with multiple downstream readouts (protein stability, ciliogenesis), single lab","pmids":["27466190"],"is_preprint":false},{"year":2017,"finding":"IFT52 recruits IFT46 to the basal body by direct interaction through residues L285 and L286 of IFT46. Ectopic nuclear expression of the IFT52 C-terminal domain redirects IFT46 to the nucleus, indicating IFT52 and IFT46 preassemble as a complex in the cytoplasm before targeting to basal bodies. The basal body localization of IFT46 depends on IFT52 but not on IFT81, IFT88, IFT122, FLA10, or DHC1b.","method":"Truncation constructs in ift46-1 mutant Chlamydomonas, ectopic nuclear targeting assay, genetic epistasis with IFT/motor mutants, site-directed mutagenesis of IFT46 residues","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis combined with ectopic localization assay and point mutagenesis identifying specific residues, multiple orthogonal methods","pmids":["28302912"],"is_preprint":false},{"year":2018,"finding":"IFT70 is essential for ciliogenesis through robust interaction with the IFT52-IFT88 dimer. Deletion of the first TPR or the C-terminal helix α36 of IFT70A greatly reduces its interaction with the IFT52-IFT88 dimer and abolishes its ability to rescue ciliogenesis in IFT70-KO cells.","method":"CRISPR/Cas9 knockout, exogenous expression rescue, deletion mutagenesis, co-immunoprecipitation, immunofluorescence","journal":"Biology open","confidence":"High","confidence_rationale":"Tier 2 / Strong — KO cells with rescue experiments and structure-function mutagenesis across multiple IFT70 deletion variants","pmids":["29654116"],"is_preprint":false},{"year":2019,"finding":"IFT52 interacts and partially co-localizes with centrin at the distal end of centrioles, where it is involved in centrin recruitment and/or maintenance. Loss of this function in Ift52−/− cells leads to centriole splitting. Additionally, a SRTD-associated IFT52 missense mutation impairs IFT-B complex assembly and IFT-B2 ciliary localization, resulting in decreased cilia length.","method":"Co-immunoprecipitation, immunofluorescence co-localization, zebrafish in vivo assays, patient cell studies with Ift52 knockout","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — co-IP and co-localization support the centrin interaction, KO cell phenotype for centriole splitting; single lab with multiple methods","pmids":["31042281"],"is_preprint":false},{"year":2022,"finding":"IFT52 variants found in short-rib polydactyly syndrome (SRPS) are specifically compromised in formation of the IFT-B holocomplex from its two subcomplexes and in interaction with heterotrimeric kinesin-II. In IFT52-KO cells expressing SRPS variants, ciliary tip localization of ICK/CILK1 and KIF17 (cargoes likely transported via IFT-B) is significantly impaired, demonstrating that impaired anterograde trafficking underlies the ciliary defects.","method":"IFT52-KO cell lines expressing SRPS variants, immunofluorescence, co-immunoprecipitation for kinesin-II interaction, ciliary tip localization assays","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO rescue with variant-specific alleles plus interaction and localization assays, single lab","pmids":["35704471"],"is_preprint":false},{"year":2022,"finding":"Knockdown of IFT52 in mouse mesenchymal stem cells disrupts IFT-B anterograde trafficking, impairs primary ciliogenesis, and blocks osteogenic differentiation. Hedgehog pathway upregulation during osteogenesis was attenuated in Ift52-silenced cells, and Smoothened Agonist-based Hh activation only incompletely restored osteogenic differentiation, placing IFT52 upstream of Hh signaling in this context.","method":"Lentiviral shRNA knockdown, osteogenic differentiation assay, Hedgehog pathway activation with SAG, immunofluorescence","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — shRNA KD with specific rescue/pathway activation experiment placing IFT52 upstream of Hh, single lab","pmids":["35839863"],"is_preprint":false},{"year":2025,"finding":"A minimal subcomplex of IFT52/IFT70 directly binds to the mitotic kinesin HSET (in vitro reconstitution). This binding induces HSET oligomerization, promoting formation of processive HSET complexes with increased microtubule-sliding ability, providing a mechanistic basis for IFT-protein-dependent centrosome clustering.","method":"In vitro reconstitution with purified proteins, TIRF microscopy, microtubule sliding assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro reconstitution with direct binding and functional readout, but preprint, single study not yet peer-reviewed","pmids":["bio_10.1101_2025.01.13.632783"],"is_preprint":true},{"year":2025,"finding":"In C. elegans sensory neurons, IFT52/OSM-6 transport rate slows significantly in cfh-1 (complement factor H homolog) mutants while IFT88/OSM-5 is unaffected, and IFT52/OSM-6 mislocalizes in photoreceptors of CFH knockout mice and in human AMD high-risk CFH Y402H photoreceptors, revealing a role for CFH in regulating IFT52 transport specifically within the IFT-B1 complex.","method":"Live imaging of IFT particle dynamics in C. elegans, immunofluorescence in mouse photoreceptors and human retinal samples, genetic mutant analysis","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 3 / Weak — preprint, imaging-based localization without biochemical mechanistic detail for the IFT52-CFH connection; indirect epistasis","pmids":["41278837"],"is_preprint":true},{"year":2026,"finding":"IFT88 and IFT52 stabilize the turnover of Chlamyopsin6 in Chlamydomonas reinhardtii, and IFT20 interacts with Chlamyopsin6, demonstrating that IFT52 is required for the stability and flagellar trafficking of a complex microbial rhodopsin.","method":"Immunocytochemistry in IFT-defective Chlamydomonas strains (ift52 mutant), co-immunoprecipitation (IFT20–Chlamyopsin6)","journal":"Biochemical and biophysical research communications","confidence":"Low","confidence_rationale":"Tier 3 / Weak — immunolocalization in IFT mutant background with single co-IP for the IFT20 interaction; IFT52 role inferred from mutant phenotype without direct interaction shown","pmids":["42214917"],"is_preprint":false}],"current_model":"IFT52 is a central scaffolding subunit of the IFT-B core complex that physically bridges the IFT88/IFT70 and IFT46/IFT81/IFT74 subcomplexes (as revealed by crystal structures and in vitro reconstitution), docks at basal body transitional fibers to facilitate IFT particle entry into cilia, directly recruits IFT46 to the basal body via specific residues, is essential for anterograde IFT-B complex integrity and ciliogenesis, acts upstream of Hedgehog signaling during osteogenic differentiation, has an extra-ciliary role at the distal centriole where it maintains centrin localization, and can directly bind and oligomerize the mitotic kinesin HSET via an IFT52/IFT70 subcomplex to promote centrosome clustering."},"narrative":{"mechanistic_narrative":"IFT52 is a central scaffolding subunit of the intraflagellar transport IFT-B core complex that is essential for anterograde transport into cilia and for ciliogenesis [PMID:20435895, PMID:25349261]. Within the ~500 kDa IFT-B core, IFT52 directly binds IFT88 and IFT46 to form a ternary unit [PMID:20435895], and crystal structures show that its C-terminal segments are buried within the IFT70 TPR superhelix (residues 330–370) and engage IFT88 (residues 281–329), while the IFT52C/IFT46C subcomplex bridges the IFT88/70/52/46 and IFT81/74/27/25/22 subcomplexes to hold the holocomplex together [PMID:25349261]. IFT52 docks at the transitional fibers around the basal body, identifying these structures as the entry site for IFT particles, and recruits IFT46 to the basal body through a cytoplasmic preassembly step [PMID:11676918, PMID:28302912]. Loss or mutation of IFT52 destabilizes partner subunits, prevents IFT-B holocomplex assembly and its interaction with kinesin-II, and impairs ciliary delivery of cargoes such as ICK/CILK1 and KIF17, manifesting in humans as short-rib polydactyly syndrome [PMID:27466190, PMID:35704471]. Beyond the cilium, IFT52 acts upstream of Hedgehog signaling to permit osteogenic differentiation [PMID:35839863] and has an extra-ciliary role at the distal centriole, where it interacts with centrin and prevents centriole splitting [PMID:31042281].","teleology":[{"year":2001,"claim":"Establishing where IFT particles enter the cilium was unresolved; localizing IFT52 to transitional fibers identified the docking site for IFT particle entry and linked the gene to flagellar assembly via the bld1 null mutant.","evidence":"Immunoelectron microscopy and immunofluorescence with genetic mutant (bld1) analysis in Chlamydomonas","pmids":["11676918"],"confidence":"High","gaps":["Did not define the molecular interactions anchoring IFT52 to transitional fibers","Did not establish IFT52's position within the IFT-B complex"]},{"year":2010,"claim":"How IFT52 fits into the IFT-B core was unknown; orthogonal biochemistry showed it directly binds IFT88 and IFT46 to form a ternary complex within the IFT-B core, defining IFT52 as a core scaffolding subunit.","evidence":"Yeast two-hybrid, bacterial coexpression, chemical cross-linking, and biochemical fractionation","pmids":["20435895"],"confidence":"High","gaps":["No structural detail on the binding interfaces","Did not address how the core links to the rest of the IFT-B complex"]},{"year":2014,"claim":"The structural logic of how IFT52 organizes the IFT-B core was unknown; crystal structures of IFT70/52 and IFT52/46 plus reconstitution showed IFT52 segments thread through IFT70 and IFT88 and that IFT52C/IFT46C bridges the two halves of the core, with dominant-negative IFT52C disrupting ciliogenesis.","evidence":"X-ray crystallography (2.5/2.3 Å), in vitro reconstitution of nonameric IFT-B core, dominant-negative overexpression in MDCK cells","pmids":["25349261"],"confidence":"High","gaps":["Did not address basal body recruitment mechanism","Did not test relevance of these interfaces to human disease alleles"]},{"year":2016,"claim":"Whether IFT52 dysfunction causes human disease was open; patient cell studies linked compound heterozygous IFT52 mutations to short-rib polydactyly syndrome through destabilization of IFT-B partners and impaired ciliogenesis.","evidence":"Patient cell western blotting, immunofluorescence cilia quantification, whole-exome sequencing","pmids":["27466190"],"confidence":"Medium","gaps":["Single lab and patient cohort","Did not resolve which molecular interaction each mutation disrupts"]},{"year":2017,"claim":"How IFT46 reaches the basal body was unclear; truncation, ectopic targeting, and point-mutagenesis assays showed IFT52 recruits IFT46 via specific residues and that the two preassemble in the cytoplasm before basal body targeting.","evidence":"Truncation constructs and ectopic nuclear targeting in ift46-1 Chlamydomonas, genetic epistasis, site-directed mutagenesis","pmids":["28302912"],"confidence":"High","gaps":["Mechanism anchoring the IFT52-IFT46 complex at the basal body not defined","Generality to mammalian cells not tested in this study"]},{"year":2018,"claim":"The contribution of IFT70 to IFT52-dependent ciliogenesis was unresolved; KO/rescue with deletion mutants showed IFT70 binds the IFT52-IFT88 dimer through its first TPR and C-terminal helix, and this interaction is required for ciliogenesis.","evidence":"CRISPR/Cas9 knockout, rescue, deletion mutagenesis, co-immunoprecipitation, immunofluorescence","pmids":["29654116"],"confidence":"High","gaps":["Did not address whether this interface is affected in disease","Functional consequences beyond ciliogenesis not examined"]},{"year":2019,"claim":"Whether IFT52 has roles outside the cilium was unknown; co-IP and co-localization revealed an extra-ciliary interaction with centrin at the distal centriole that prevents centriole splitting, alongside an SRTD missense allele impairing IFT-B2 ciliary localization.","evidence":"Co-immunoprecipitation, co-localization, zebrafish in vivo assays, patient cells with Ift52 knockout","pmids":["31042281"],"confidence":"Medium","gaps":["Centrin-IFT52 interaction shown by co-IP without structural detail","Mechanism linking centrin maintenance to centriole cohesion unresolved"]},{"year":2022,"claim":"The molecular basis by which SRPS IFT52 variants impair cilia was unclear; KO-rescue with variant alleles showed they fail to assemble the IFT-B holocomplex and to bind kinesin-II, impairing anterograde delivery of ICK/CILK1 and KIF17.","evidence":"IFT52-KO cells expressing SRPS variants, co-IP for kinesin-II, ciliary tip localization assays","pmids":["35704471"],"confidence":"Medium","gaps":["Single lab","Direct structural mapping of kinesin-II contact not provided"]},{"year":2022,"claim":"The relevance of IFT52 to differentiation signaling was untested; shRNA knockdown placed IFT52 upstream of Hedgehog signaling, with its loss blocking primary ciliogenesis and osteogenic differentiation only partially rescued by Hedgehog activation.","evidence":"Lentiviral shRNA knockdown, osteogenic differentiation assay, Hedgehog activation with SAG, immunofluorescence","pmids":["35839863"],"confidence":"Medium","gaps":["Incomplete rescue indicates additional cilia-dependent inputs not identified","Single cell-type model"]},{"year":2025,"claim":"Whether IFT subunits directly modulate mitotic motors was unknown; in vitro reconstitution showed an IFT52/IFT70 subcomplex directly binds and oligomerizes HSET, generating processive microtubule-sliding complexes that support centrosome clustering.","evidence":"In vitro reconstitution with purified proteins, TIRF microscopy, microtubule sliding assay (preprint)","pmids":["bio_10.1101_2025.01.13.632783"],"confidence":"Medium","gaps":["Preprint, not yet peer-reviewed","In-cell relevance to centrosome clustering not demonstrated biochemically"]},{"year":2025,"claim":"Whether external regulators tune IFT52 transport was unexplored; imaging in C. elegans and mouse/human photoreceptors showed CFH mutation slows and mislocalizes IFT52/OSM-6 specifically within IFT-B1, without affecting IFT88.","evidence":"Live imaging of IFT dynamics in C. elegans, immunofluorescence in mouse/human photoreceptors, genetic mutants (preprint)","pmids":["41278837"],"confidence":"Low","gaps":["Preprint with imaging-based, indirect epistasis and no biochemical CFH-IFT52 link","Mechanism of subcomplex-specific regulation unknown"]},{"year":2026,"claim":"Whether IFT52 controls membrane-protein cargo stability was open; immunolocalization in ift52 mutant Chlamydomonas indicated IFT52 (with IFT88) is required for stability and flagellar trafficking of Chlamyopsin6.","evidence":"Immunocytochemistry in IFT-defective Chlamydomonas strains, co-IP (IFT20-Chlamyopsin6)","pmids":["42214917"],"confidence":"Low","gaps":["IFT52 role inferred from mutant phenotype without direct interaction","Single co-IP only for the IFT20 partner, not IFT52"]},{"year":null,"claim":"How IFT52's extra-ciliary activities (distal centriole centrin maintenance, HSET-dependent centrosome clustering) are mechanistically coordinated with its core IFT-B scaffolding role, and how these are regulated in cells, remains open.","evidence":"","pmids":[],"confidence":"Low","gaps":["No structural model of the IFT52-centrin interaction","In-cell validation of the IFT52/IFT70-HSET mechanism lacking","Regulatory inputs governing IFT52 partitioning between ciliary and centriolar pools unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[1,2,4]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[2,9]}],"localization":[{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[0,6]},{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[2,3,7]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[0]}],"pathway":[{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[2,7]},{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[1,7]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[8]},{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[2,3]}],"complexes":["IFT-B core complex","IFT52/IFT70 subcomplex","IFT52/IFT46 subcomplex"],"partners":["IFT88","IFT46","IFT70","IFT81","IFT74","HSET","CENTRIN"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9Y366","full_name":"Intraflagellar transport protein 52 homolog","aliases":["Protein NGD5 homolog"],"length_aa":437,"mass_kda":49.7,"function":"Involved in ciliogenesis as part of a complex involved in intraflagellar transport (IFT), the bi-directional movement of particles required for the assembly, maintenance and functioning of primary cilia (PubMed:27466190). Required for the anterograde transport of IFT88 (PubMed:27466190)","subcellular_location":"Cell projection, cilium","url":"https://www.uniprot.org/uniprotkb/Q9Y366/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/IFT52","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1208,"dependency_fraction":0.0008278145695364238},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"HSPB11","stoichiometry":10.0}],"url":"https://opencell.sf.czbiohub.org/search/IFT52","total_profiled":1310},"omim":[{"mim_id":"621121","title":"CILIA- AND FLAGELLA-ASSOCIATED PROTEIN 54; CFAP54","url":"https://www.omim.org/entry/621121"},{"mim_id":"620742","title":"INTRAFLAGELLAR TRANSPORT 70B; IFT70B","url":"https://www.omim.org/entry/620742"},{"mim_id":"620741","title":"INTRAFLAGELLAR TRANSPORT 70A; IFT70A","url":"https://www.omim.org/entry/620741"},{"mim_id":"620506","title":"INTRAFLAGELLAR TRANSPORT 46; IFT46","url":"https://www.omim.org/entry/620506"},{"mim_id":"620084","title":"SPERMATOGENIC FAILURE 76; SPGF76","url":"https://www.omim.org/entry/620084"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Microtubules","reliability":"Approved"},{"location":"Primary cilium","reliability":"Additional"},{"location":"Basal body","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/IFT52"},"hgnc":{"alias_symbol":["CGI-53","NGD5","dJ1028D15.1","NGD2"],"prev_symbol":["C20orf9"]},"alphafold":{"accession":"Q9Y366","domains":[{"cath_id":"3.40.50.880","chopping":"7-148_158-263","consensus_level":"high","plddt":91.3426,"start":7,"end":263},{"cath_id":"-","chopping":"357-421","consensus_level":"high","plddt":85.8623,"start":357,"end":421}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9Y366","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9Y366-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9Y366-F1-predicted_aligned_error_v6.png","plddt_mean":84.25},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=IFT52","jax_strain_url":"https://www.jax.org/strain/search?query=IFT52"},"sequence":{"accession":"Q9Y366","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9Y366.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9Y366/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9Y366"}},"corpus_meta":[{"pmid":"11676918","id":"PMC_11676918","title":"Localization of intraflagellar transport protein IFT52 identifies basal body transitional fibers as the docking site for IFT particles.","date":"2001","source":"Current biology : CB","url":"https://pubmed.ncbi.nlm.nih.gov/11676918","citation_count":313,"is_preprint":false},{"pmid":"25349261","id":"PMC_25349261","title":"Crystal structures of IFT70/52 and IFT52/46 provide insight into intraflagellar transport B core complex assembly.","date":"2014","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/25349261","citation_count":102,"is_preprint":false},{"pmid":"20435895","id":"PMC_20435895","title":"Direct interactions of intraflagellar transport complex B proteins IFT88, IFT52, and IFT46.","date":"2010","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/20435895","citation_count":68,"is_preprint":false},{"pmid":"26880018","id":"PMC_26880018","title":"A homozygous nonsense variant in IFT52 is associated with a human skeletal 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neurons","date":"2025-10-13","source":"bioRxiv","url":"https://doi.org/10.1101/2025.10.10.681644","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.01.13.632783","title":"In vitro reconstitution defines the mechanistic basis of HSET motor activity regulation by IntraFlagellar Transport proteins","date":"2025-01-14","source":"bioRxiv","url":"https://doi.org/10.1101/2025.01.13.632783","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.12.27.630506","title":"Phototropin localization and interactions regulates photophysiological  processes in  <i>Chlamydomonas reinhardtii</i>","date":"2024-12-27","source":"bioRxiv","url":"https://doi.org/10.1101/2024.12.27.630506","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":11857,"output_tokens":3442,"usd":0.043601,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10843,"output_tokens":4249,"usd":0.08022,"stage2_stop_reason":"end_turn"},"total_usd":0.123821,"stage1_batch_id":"msgbatch_01DUPACZi7AAWwuZiUjseQF4","stage2_batch_id":"msgbatch_018yt7chE3f48PEFtDwtj6AE","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2001,\n      \"finding\": \"IFT52 localizes by immunofluorescence and immunoelectron microscopy to two horseshoe-shaped rings around the basal bodies, specifically associated with the periphery of transitional fibers, identifying transitional fibers as the docking site for IFT particles entering the flagellar compartment. The flagellaless bld1 mutant carries a deletion in the IFT52 gene and completely lacks IFT52 protein.\",\n      \"method\": \"Immunofluorescence, immunoelectron microscopy, cDNA cloning, genetic mutant analysis (bld1)\",\n      \"journal\": \"Current biology : CB\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct localization by immunoelectron microscopy with genetic confirmation via bld1 null mutant, replicated by immunofluorescence\",\n      \"pmids\": [\"11676918\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"IFT52 directly interacts with IFT88 and IFT46 within the IFT-B core complex, and these three proteins together form a ternary complex. Chemical cross-linking confirmed the IFT52-IFT88 interaction. IFT52 is part of the ~500 kDa IFT-B core that also contains IFT88, IFT81, IFT74/72, IFT46, IFT27, IFT25, and IFT22.\",\n      \"method\": \"Yeast two-hybrid, bacterial coexpression, chemical cross-linking, biochemical fractionation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — multiple orthogonal methods (Y2H, bacterial coexpression, cross-linking) in a single study establishing direct binary and ternary interactions\",\n      \"pmids\": [\"20435895\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Crystal structures of IFT70/52 (2.5 Å) and IFT52/46 (2.3 Å) subcomplexes revealed that IFT52 residues 330–370 are buried within the IFT70 tetratricopeptide repeat superhelix; IFT88 binds IFT52 residues 281–329; and the IFT52C/IFT46C subcomplex is essential for IFT-B core integrity by mediating interaction between the IFT88/70/52/46 and IFT81/74/27/25/22 subcomplexes. Overexpression of mammalian IFT52C acts as a dominant-negative, causing IFT protein mislocalization and disrupted ciliogenesis in MDCK cells.\",\n      \"method\": \"X-ray crystallography (2.5 Å and 2.3 Å), in vitro reconstitution of nonameric IFT-B core, dominant-negative overexpression in MDCK cells\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — high-resolution crystal structures combined with biochemical reconstitution and functional cell-based validation\",\n      \"pmids\": [\"25349261\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"IFT52 compound heterozygous mutations in a short-rib polydactyly syndrome patient result in reduced IFT52 protein, leading to reduced levels of IFT74, IFT81, IFT88, and ARL13B, a 60% reduction in cilia formation, and loss of cilia length regulation, demonstrating IFT52 is essential for anterograde IFT-B complex integrity and ciliogenesis.\",\n      \"method\": \"Patient cell studies, western blotting, immunofluorescence cilia quantification, whole-exome sequencing\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — patient cell-based loss-of-function with multiple downstream readouts (protein stability, ciliogenesis), single lab\",\n      \"pmids\": [\"27466190\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"IFT52 recruits IFT46 to the basal body by direct interaction through residues L285 and L286 of IFT46. Ectopic nuclear expression of the IFT52 C-terminal domain redirects IFT46 to the nucleus, indicating IFT52 and IFT46 preassemble as a complex in the cytoplasm before targeting to basal bodies. The basal body localization of IFT46 depends on IFT52 but not on IFT81, IFT88, IFT122, FLA10, or DHC1b.\",\n      \"method\": \"Truncation constructs in ift46-1 mutant Chlamydomonas, ectopic nuclear targeting assay, genetic epistasis with IFT/motor mutants, site-directed mutagenesis of IFT46 residues\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis combined with ectopic localization assay and point mutagenesis identifying specific residues, multiple orthogonal methods\",\n      \"pmids\": [\"28302912\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"IFT70 is essential for ciliogenesis through robust interaction with the IFT52-IFT88 dimer. Deletion of the first TPR or the C-terminal helix α36 of IFT70A greatly reduces its interaction with the IFT52-IFT88 dimer and abolishes its ability to rescue ciliogenesis in IFT70-KO cells.\",\n      \"method\": \"CRISPR/Cas9 knockout, exogenous expression rescue, deletion mutagenesis, co-immunoprecipitation, immunofluorescence\",\n      \"journal\": \"Biology open\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — KO cells with rescue experiments and structure-function mutagenesis across multiple IFT70 deletion variants\",\n      \"pmids\": [\"29654116\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"IFT52 interacts and partially co-localizes with centrin at the distal end of centrioles, where it is involved in centrin recruitment and/or maintenance. Loss of this function in Ift52−/− cells leads to centriole splitting. Additionally, a SRTD-associated IFT52 missense mutation impairs IFT-B complex assembly and IFT-B2 ciliary localization, resulting in decreased cilia length.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence co-localization, zebrafish in vivo assays, patient cell studies with Ift52 knockout\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — co-IP and co-localization support the centrin interaction, KO cell phenotype for centriole splitting; single lab with multiple methods\",\n      \"pmids\": [\"31042281\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"IFT52 variants found in short-rib polydactyly syndrome (SRPS) are specifically compromised in formation of the IFT-B holocomplex from its two subcomplexes and in interaction with heterotrimeric kinesin-II. In IFT52-KO cells expressing SRPS variants, ciliary tip localization of ICK/CILK1 and KIF17 (cargoes likely transported via IFT-B) is significantly impaired, demonstrating that impaired anterograde trafficking underlies the ciliary defects.\",\n      \"method\": \"IFT52-KO cell lines expressing SRPS variants, immunofluorescence, co-immunoprecipitation for kinesin-II interaction, ciliary tip localization assays\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO rescue with variant-specific alleles plus interaction and localization assays, single lab\",\n      \"pmids\": [\"35704471\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Knockdown of IFT52 in mouse mesenchymal stem cells disrupts IFT-B anterograde trafficking, impairs primary ciliogenesis, and blocks osteogenic differentiation. Hedgehog pathway upregulation during osteogenesis was attenuated in Ift52-silenced cells, and Smoothened Agonist-based Hh activation only incompletely restored osteogenic differentiation, placing IFT52 upstream of Hh signaling in this context.\",\n      \"method\": \"Lentiviral shRNA knockdown, osteogenic differentiation assay, Hedgehog pathway activation with SAG, immunofluorescence\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — shRNA KD with specific rescue/pathway activation experiment placing IFT52 upstream of Hh, single lab\",\n      \"pmids\": [\"35839863\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"A minimal subcomplex of IFT52/IFT70 directly binds to the mitotic kinesin HSET (in vitro reconstitution). This binding induces HSET oligomerization, promoting formation of processive HSET complexes with increased microtubule-sliding ability, providing a mechanistic basis for IFT-protein-dependent centrosome clustering.\",\n      \"method\": \"In vitro reconstitution with purified proteins, TIRF microscopy, microtubule sliding assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro reconstitution with direct binding and functional readout, but preprint, single study not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.01.13.632783\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In C. elegans sensory neurons, IFT52/OSM-6 transport rate slows significantly in cfh-1 (complement factor H homolog) mutants while IFT88/OSM-5 is unaffected, and IFT52/OSM-6 mislocalizes in photoreceptors of CFH knockout mice and in human AMD high-risk CFH Y402H photoreceptors, revealing a role for CFH in regulating IFT52 transport specifically within the IFT-B1 complex.\",\n      \"method\": \"Live imaging of IFT particle dynamics in C. elegans, immunofluorescence in mouse photoreceptors and human retinal samples, genetic mutant analysis\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — preprint, imaging-based localization without biochemical mechanistic detail for the IFT52-CFH connection; indirect epistasis\",\n      \"pmids\": [\"41278837\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"IFT88 and IFT52 stabilize the turnover of Chlamyopsin6 in Chlamydomonas reinhardtii, and IFT20 interacts with Chlamyopsin6, demonstrating that IFT52 is required for the stability and flagellar trafficking of a complex microbial rhodopsin.\",\n      \"method\": \"Immunocytochemistry in IFT-defective Chlamydomonas strains (ift52 mutant), co-immunoprecipitation (IFT20–Chlamyopsin6)\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — immunolocalization in IFT mutant background with single co-IP for the IFT20 interaction; IFT52 role inferred from mutant phenotype without direct interaction shown\",\n      \"pmids\": [\"42214917\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"IFT52 is a central scaffolding subunit of the IFT-B core complex that physically bridges the IFT88/IFT70 and IFT46/IFT81/IFT74 subcomplexes (as revealed by crystal structures and in vitro reconstitution), docks at basal body transitional fibers to facilitate IFT particle entry into cilia, directly recruits IFT46 to the basal body via specific residues, is essential for anterograde IFT-B complex integrity and ciliogenesis, acts upstream of Hedgehog signaling during osteogenic differentiation, has an extra-ciliary role at the distal centriole where it maintains centrin localization, and can directly bind and oligomerize the mitotic kinesin HSET via an IFT52/IFT70 subcomplex to promote centrosome clustering.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"IFT52 is a central scaffolding subunit of the intraflagellar transport IFT-B core complex that is essential for anterograde transport into cilia and for ciliogenesis [#1, #2]. Within the ~500 kDa IFT-B core, IFT52 directly binds IFT88 and IFT46 to form a ternary unit [#1], and crystal structures show that its C-terminal segments are buried within the IFT70 TPR superhelix (residues 330–370) and engage IFT88 (residues 281–329), while the IFT52C/IFT46C subcomplex bridges the IFT88/70/52/46 and IFT81/74/27/25/22 subcomplexes to hold the holocomplex together [#2]. IFT52 docks at the transitional fibers around the basal body, identifying these structures as the entry site for IFT particles, and recruits IFT46 to the basal body through a cytoplasmic preassembly step [#0, #4]. Loss or mutation of IFT52 destabilizes partner subunits, prevents IFT-B holocomplex assembly and its interaction with kinesin-II, and impairs ciliary delivery of cargoes such as ICK/CILK1 and KIF17, manifesting in humans as short-rib polydactyly syndrome [#3, #7]. Beyond the cilium, IFT52 acts upstream of Hedgehog signaling to permit osteogenic differentiation [#8] and has an extra-ciliary role at the distal centriole, where it interacts with centrin and prevents centriole splitting [#6].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Establishing where IFT particles enter the cilium was unresolved; localizing IFT52 to transitional fibers identified the docking site for IFT particle entry and linked the gene to flagellar assembly via the bld1 null mutant.\",\n      \"evidence\": \"Immunoelectron microscopy and immunofluorescence with genetic mutant (bld1) analysis in Chlamydomonas\",\n      \"pmids\": [\"11676918\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the molecular interactions anchoring IFT52 to transitional fibers\", \"Did not establish IFT52's position within the IFT-B complex\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"How IFT52 fits into the IFT-B core was unknown; orthogonal biochemistry showed it directly binds IFT88 and IFT46 to form a ternary complex within the IFT-B core, defining IFT52 as a core scaffolding subunit.\",\n      \"evidence\": \"Yeast two-hybrid, bacterial coexpression, chemical cross-linking, and biochemical fractionation\",\n      \"pmids\": [\"20435895\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No structural detail on the binding interfaces\", \"Did not address how the core links to the rest of the IFT-B complex\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"The structural logic of how IFT52 organizes the IFT-B core was unknown; crystal structures of IFT70/52 and IFT52/46 plus reconstitution showed IFT52 segments thread through IFT70 and IFT88 and that IFT52C/IFT46C bridges the two halves of the core, with dominant-negative IFT52C disrupting ciliogenesis.\",\n      \"evidence\": \"X-ray crystallography (2.5/2.3 Å), in vitro reconstitution of nonameric IFT-B core, dominant-negative overexpression in MDCK cells\",\n      \"pmids\": [\"25349261\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not address basal body recruitment mechanism\", \"Did not test relevance of these interfaces to human disease alleles\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Whether IFT52 dysfunction causes human disease was open; patient cell studies linked compound heterozygous IFT52 mutations to short-rib polydactyly syndrome through destabilization of IFT-B partners and impaired ciliogenesis.\",\n      \"evidence\": \"Patient cell western blotting, immunofluorescence cilia quantification, whole-exome sequencing\",\n      \"pmids\": [\"27466190\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab and patient cohort\", \"Did not resolve which molecular interaction each mutation disrupts\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"How IFT46 reaches the basal body was unclear; truncation, ectopic targeting, and point-mutagenesis assays showed IFT52 recruits IFT46 via specific residues and that the two preassemble in the cytoplasm before basal body targeting.\",\n      \"evidence\": \"Truncation constructs and ectopic nuclear targeting in ift46-1 Chlamydomonas, genetic epistasis, site-directed mutagenesis\",\n      \"pmids\": [\"28302912\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism anchoring the IFT52-IFT46 complex at the basal body not defined\", \"Generality to mammalian cells not tested in this study\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"The contribution of IFT70 to IFT52-dependent ciliogenesis was unresolved; KO/rescue with deletion mutants showed IFT70 binds the IFT52-IFT88 dimer through its first TPR and C-terminal helix, and this interaction is required for ciliogenesis.\",\n      \"evidence\": \"CRISPR/Cas9 knockout, rescue, deletion mutagenesis, co-immunoprecipitation, immunofluorescence\",\n      \"pmids\": [\"29654116\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not address whether this interface is affected in disease\", \"Functional consequences beyond ciliogenesis not examined\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Whether IFT52 has roles outside the cilium was unknown; co-IP and co-localization revealed an extra-ciliary interaction with centrin at the distal centriole that prevents centriole splitting, alongside an SRTD missense allele impairing IFT-B2 ciliary localization.\",\n      \"evidence\": \"Co-immunoprecipitation, co-localization, zebrafish in vivo assays, patient cells with Ift52 knockout\",\n      \"pmids\": [\"31042281\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Centrin-IFT52 interaction shown by co-IP without structural detail\", \"Mechanism linking centrin maintenance to centriole cohesion unresolved\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"The molecular basis by which SRPS IFT52 variants impair cilia was unclear; KO-rescue with variant alleles showed they fail to assemble the IFT-B holocomplex and to bind kinesin-II, impairing anterograde delivery of ICK/CILK1 and KIF17.\",\n      \"evidence\": \"IFT52-KO cells expressing SRPS variants, co-IP for kinesin-II, ciliary tip localization assays\",\n      \"pmids\": [\"35704471\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Direct structural mapping of kinesin-II contact not provided\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"The relevance of IFT52 to differentiation signaling was untested; shRNA knockdown placed IFT52 upstream of Hedgehog signaling, with its loss blocking primary ciliogenesis and osteogenic differentiation only partially rescued by Hedgehog activation.\",\n      \"evidence\": \"Lentiviral shRNA knockdown, osteogenic differentiation assay, Hedgehog activation with SAG, immunofluorescence\",\n      \"pmids\": [\"35839863\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Incomplete rescue indicates additional cilia-dependent inputs not identified\", \"Single cell-type model\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Whether IFT subunits directly modulate mitotic motors was unknown; in vitro reconstitution showed an IFT52/IFT70 subcomplex directly binds and oligomerizes HSET, generating processive microtubule-sliding complexes that support centrosome clustering.\",\n      \"evidence\": \"In vitro reconstitution with purified proteins, TIRF microscopy, microtubule sliding assay (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.01.13.632783\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not yet peer-reviewed\", \"In-cell relevance to centrosome clustering not demonstrated biochemically\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Whether external regulators tune IFT52 transport was unexplored; imaging in C. elegans and mouse/human photoreceptors showed CFH mutation slows and mislocalizes IFT52/OSM-6 specifically within IFT-B1, without affecting IFT88.\",\n      \"evidence\": \"Live imaging of IFT dynamics in C. elegans, immunofluorescence in mouse/human photoreceptors, genetic mutants (preprint)\",\n      \"pmids\": [\"41278837\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Preprint with imaging-based, indirect epistasis and no biochemical CFH-IFT52 link\", \"Mechanism of subcomplex-specific regulation unknown\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Whether IFT52 controls membrane-protein cargo stability was open; immunolocalization in ift52 mutant Chlamydomonas indicated IFT52 (with IFT88) is required for stability and flagellar trafficking of Chlamyopsin6.\",\n      \"evidence\": \"Immunocytochemistry in IFT-defective Chlamydomonas strains, co-IP (IFT20-Chlamyopsin6)\",\n      \"pmids\": [\"42214917\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"IFT52 role inferred from mutant phenotype without direct interaction\", \"Single co-IP only for the IFT20 partner, not IFT52\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How IFT52's extra-ciliary activities (distal centriole centrin maintenance, HSET-dependent centrosome clustering) are mechanistically coordinated with its core IFT-B scaffolding role, and how these are regulated in cells, remains open.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model of the IFT52-centrin interaction\", \"In-cell validation of the IFT52/IFT70-HSET mechanism lacking\", \"Regulatory inputs governing IFT52 partitioning between ciliary and centriolar pools unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [1, 2, 4]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [2, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [0, 6]},\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [2, 3, 7]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [2, 7]},\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [1, 7]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [8]},\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [2, 3]}\n    ],\n    \"complexes\": [\"IFT-B core complex\", \"IFT52/IFT70 subcomplex\", \"IFT52/IFT46 subcomplex\"],\n    \"partners\": [\"IFT88\", \"IFT46\", \"IFT70\", \"IFT81\", \"IFT74\", \"HSET\", \"centrin\"],\n    \"other_free_text\": []\n  }\n}\n```","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}